One of the most common injuries sustained by construction workers, maintenance crews and those engaged in similar work involves the back due to stresses placed on it by lifting and carrying heavy and awkward objects. Injuries to the hands and feet are also relatively common as workers are frequently required to lift and move heavy objects which do not have proper handles and consequently are difficult to grasp. Objects of this category include but are not limited to maintenance hole covers, catch basin covers and their respective frames.
Numerous existing lifting devices utilize pincers or friction pads with the opposinglever concept in their application to convey a specific item such as masonry, meat and logs. In this regard, the prior art is replete with patents relating to devices and methods designed to assist in the lifting and moving of objects.
Some examples of these prior patents include recently issued U.S. Pat. No. 5,713,559, dated Feb. 3, 1998, to McClarin, et al that describes a device intended to raise fence posts and to lift certain objects including manhole covers. This patent discloses a first-class lever system in which a hook, at one end of an elongate arm, is attached to a manhole cover that in turn is raised by forcing downwardly the distal end of the arm. The fulcrum of the lever is located close to the end to which the manhole cover is connected. This device provides a lifting system, but is not readily adaptable to moving and subsequently positioning the manhole cover. U.S. Pat. No. 5,791,855, which issued Aug. 11, 1998, to Dixon, and U.S. Pat. No. 5,848,668, which issued Dec. 15, 1998, to Kafrissen, both relate to arrangements having a frame with wheels and means to raise and carry objects by first raising the object to a sufficient height to allow the carrying device to slide underneath. In other words, some lifting by the user is required before the device can be used.
In spite of the previous efforts to design an effective lifting device, there remains a need for a convenient and safe means of lifting relatively heavy objects while safeguarding the users from back and/or leg and feet injuries.